A Commercial Clay-Based Material as a Carrier for Targeted Lysozyme Delivery in Animal Feed

The controlled supply of bioactive molecules is a subject of debate in animal nutrition. The release of bioactive molecules in the target organ, in this case the intestine, results in improved feed, as well as having a lower environmental impact. However, the degradation of bioactive molecules' in transit in the gastrointestinal passage is still an unresolved issue. This paper discusses the feasibility of a simple and cost-effective procedure to bypass the degradation problem. A solid/liquid adsorption procedure was applied, and the operating parameters (pH, reaction time, and LY initial concentration) were studied. Lysozyme is used in this work as a representative bioactive molecule, while Adsorbo®, a commercial mixture of clay minerals and zeolites which meets current feed regulations, is used as the carrier. A maximum LY loading of 32 mgLY/gAD (LY(32)-AD) was obtained, with fixing pH in the range 7.5-8, initial LY content at 37.5 mgLY/gAD, and reaction time at 30 min. A full characterisation of the hybrid organoclay highlighted that LY molecules were homogeneously spread on the carrier's surface, where the LY-carrier interaction was mainly due to charge interaction. Preliminary release tests performed on the LY(32)-AD synthesised sample showed a higher releasing capacity, raising the pH from 3 to 7. In addition, a preliminary Trolox equivalent antioxidant capacity (TEAC) assay showed an antioxidant capacity for the LY of 1.47 ± 0.18 µmol TroloxEq/g with an inhibition percentage of 33.20 ± 3.94%.

Reduced Graphene Oxide/Waste-Derived TiO2 Composite Membranes: Preliminary Study of a New Material for Hybrid Wastewater Treatment

This work reports the preliminary results of the development of composite self-assembling membranes obtained by the combination of reduced graphene oxide (rGO) with commercial Degussa P25 titanium dioxide (TiO₂). The purpose is to demonstrate the possibility of combining, in the same self-standing material, the capability to treat wastewater containing both inorganic and organic pollutants by exploiting the established ability of rGO to capture metal ions together with that of TiO₂ to degrade organic substances. Moreover, this study also investigates the potential photocatalytic properties of tionite (TIO), to demonstrate the feasibility of replacing commercial TiO₂ with such waste-derived TiO₂-containing material, fulfilling a circular economy approach. Thus, rGO-TiO₂ and rGO-TIO composite membranes, 1:1 by weight, were prepared and characterized by SEM-EDX, XRD, thermogravimetry, as well as by Raman and UV-Vis spectroscopies to verify the effective and homogeneous integration of the two components. Then, they were tested towards 3-mg L^-1 aqueous synthetic solutions of Fe³⁺ and Cu²⁺ ions to evaluate their metal adsorption ability, with values of the order of 0.1-0.2 mmol g_membrane^-1, comparable or even slightly higher than those of pristine rGO. Finally, the ability of the composites to degrade a common organic pesticide, i.e., Imidacloprid^®, was assessed in preliminary photocatalysis experiments, in which maximum degradation efficiencies of 25% (after 3 h) for rGO-TiO₂ and of 21% (after 1 h) for rGO-TIO were found. The result of tionite-containing membranes is particularly promising and worthy of further investigation, given that the anatase content of tionite is roughly 1/6 of the one in commercial TiO₂.

Abstract 2082: NMS-E668, a potent and selective RET kinase inhibitor characterized by specificity towards VEGFR2 and high antitumor efficacy against RET-driven models

RET, a receptor tyrosine kinase (RTK) expressed mainly in neural crest-derived tissues, plays a role in cell growth and differentiation and its physiological activation depends upon binding to the GDNF family. Genetic aberrations leading to constitutive RET activation are well-established as oncogenic events. Activating point mutations of RET, for example, are present in ca. 70% of medullary thyroid carcinoma patients including all hereditary cases, while RET gene rearrangements resulting in production of activated RET fusion proteins occur in approximately 10% of sporadic papillary thyroid carcinomas. More recently, recurring RET gene rearrangements have also been found in 1-2 % of lung adenocarcinomas and subsets of other solid tumors including colorectal and salivary gland carcinomas. Thus RET kinase represents an actionable therapeutic target in multiple clinical settings with high medical need. Consequently several small-molecule inhibitors targeting this kinase have been explored in clinical settings. A common feature of most advanced agents is their lack of selectivity and in particular their potent cross-reactivity against VEGFR2, an RTK whose inhibition is associated with serious, dose-limiting cardiovascular toxicity. Indeed, the high homology between the two kinases renders identification of ATP competitive compounds that selectively inhibit RET over VEGFR2 a highly challenging task. Here we describe the preclinical activity of NMS-E668, a potent and selective ATP-competitive RET inhibitor characterized by favorable activity, selectivity and ADME profiles. Biochemically, NMS-E668 has an excellent selectivity profile against a panel of >50 kinases, notably including >10-fold selectivity over VEGFR2. Selectivity of NMS-E668 for RET vs. VEGFR2 was confirmed in NIH-3T3 cells engineered to express activated forms of these kinases. NMS-E668 potently (IC50 circa 50 nM) and selectively inhibited proliferation of RET-dependent tumor cells, including TT medullary carcinoma cells harboring a RET C634W activating point mutation and LC2/ad lung carcinoma cells bearing the oncogenic fusion protein CCDC6-RET. NMS-E668 also potently inhibited IL3-independent growth of Ba/F3 cells expressing KIF5B-RET, the RET rearrangement that is most commonly found in lung adenocarcinomas. Cellular mechanism studies confirmed that NMS-E668 inhibits RET autophosphorylation and downstream signaling at doses consistent with antiproliferative activity. Tested in vivo against KIF5B-RET-driven Ba/F3 tumors, NMS-E668 displayed >90% tumor growth inhibition accompanied by target modulation following oral administration at 10 and 20 mg/kg, with prolonged tumor regressions observed at the higher dose. Thus NMS-E668, a potent and VEGFR2-sparing RET inhibitor is an innovative and highly promising candidate for further development.

Citation Format: Elena Ardini, Patrizia Banfi, Nilla Avanzi, Marina Ciomei, Paolo Polucci, Alessandra Cirla, Antonella Ermoli, Ilaria Motto, Elena Casale, Giulia Canevari, Cinzia Cristiani, Sonia Troiani, Federico Riccardi Sirtori, Nadia Amboldi, Dario Ballinari, Francesco Caprera, Eduard Felder, Arturo Galvani, Daniele Donati, Antonella Isacchi, Maria Menichincheri. NMS-E668, a potent and selective RET kinase inhibitor characterized by specificity towards VEGFR2 and high antitumor efficacy against RET-driven models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2082. doi:10.1158/1538-7445.AM2017-2082

Recovery of valuable metals from electronic scraps by clays and organo-clays: Study on bi-ionic model solutions

The demand of valuable metals, as precious metals and rare earths, is constantly increasing in the global market, as many and different technological applications exploit these materials because of their unique properties. Since natural resources are located just in focused areas, an interesting possibility could be the recovery of metals from Waste Electrical and Electronic Equipment (WEEE). The aim of this work is to evaluate the recovery potentialities of clays and organo-clay based systems towards the metals contained in the solutions of electronic scraps dissolved in strong acid, by preliminary tests on bi-ionic model solutions. Lanthanum has been chosen as representative of the rare earths while copper has been considered since it is by far the most used metal in electric and electronic equipment. The considered sorbents are a montmorillonitic clay and two polyamine based organo-clays. Uptake and release processes have been carried out in order to assess the performances of these solids and to evaluate the uptake and release mechanisms. The results showed that the cationic exchange is the prevailing mechanism in the case of pristine clay, while both coordinating effect due to amino groups and cationic exchange occur in the case of modified clays, respectively accounting for copper and lanthanum uptake. Furthermore the pH was found having a great influence in both the adsorption and desorption phenomena.

Abstract A179: NMS-P113, a novel orally available JAK2 selective inhibitor

The Janus Kinases (JAK1, JAK2, JAK3, TYK2) are non-receptor tyrosine kinases that play important roles in hematopoiesis and immune response. In particular, gene ablation of JAK1 or JAK2 in the mouse is incompatible with life, due to neurological defects/immunodeficency and lack of erythropoiesis, respectively, whereas that of JAK3 or TYK2 is associated with severe immunodeficiency.

Activating mutations of JAKs are found in association with malignant transformation. The best characterized gain-of-function mutation, JAK2-V617F in the pseudo-kinase domain of JAK2, is present in hematopoietic cells of patients with myeloproliferative disorders (MPD). In particular, the JAK2-V617F mutation is found in >95% of patients with polycythemia vera (PV), circa 50% of patients with essential thrombocythemia (ET), and circa 50% of myelofibrosis (MF) patients. Recently, a central role of JAK2 has been described in upregulation of the immune checkpoint component PD-L1 mediated by IFN-γ or by chromosome 9p24.1 amplification, suggesting that its inhibition might provide a new strategy to increase immune-mediated tumor inhibition in specific contexts.

Although JAK inhibitors have been approved in oncological and autoimmune settings (e.g. the JAK1/JAK2 inhibitor ruxolitinib in MF and the pan-JAK inhibitor tofacitinib in rheumatoid arthritis) and multiple agents are in clinical testing, JAK2 selective compounds might be provide an advantage for long-term MPD therapy or in association with immunotherapy, given that inhibition of other JAK family members leads to immunosuppressive effects.

Due to high homology amongst JAK family kinases within the ATP binding pocket, discovery of selective JAK2 inhibitors has represented a significant challenge. Here, we report the characterization of NMS-P113, a potent and selective JAK2 inhibitor. Screening of the NMS compound collection led to the identification of a pyrrole series with promising activity against JAK2. An optimization program led to identification of the potent and orally bioavailable JAK2 inhibitor NMS-P113. In biochemical assay this compound possesses low nanomolar potency against JAK2 (IC50 3 nM), with preferential activity over other JAK family members and high selectivity against a panel of 60 further kinases. In cellular assay, NMS-P113 potently inhibits proliferation of the JAK2 dependent SET-2 human megakaryoblastic leukemia line, derived from an ET patient and which harbors the JAK2-V617F mutation, as well as of Ba/F3 cells engineered to express constitutively activated JAK2 (IC50s circa 200 nM). NMS-P113 is 10-fold less active against the DERL-7 T-cell lymphoma cell line (which is dependent upon JAK1/JAK3) and has poor antiproliferative activity in JAK independent lines. Oral administration of NMS-P113 results in dose-related normalization of spleen weight and erythrocyte precursors count in an erythropoietin-induced model of PV in the mouse. Mechanism of action of NMS-P113, as assessed by inhibition of P-STAT5, was confirmed in vitro and in vivo.

A favorable ADME profile with high oral bioavailability, together with permissive therapeutic safety margins in test species, indicate that NMS-P113 is suitable for further development, affording the possibility of reduced undesirable immunosuppressive activities compared to inhibitors that target multiple members of the JAK family.

Citation Format: Paola Gnocchi, Maria Gabriella Brasca, Nadia Amboldi, Nilla Avanzi, Simona Bindi, Giulia Canevari, Daniele Casero, Roberta Ceruti, Marina Ciomei, Sabrina Cribioli, Cinzia Cristiani, Marcella Nesi, Wilma Pastori, Veronica Patton, Cinzia Pellizzoni, Gemma Texido, Elena Ardini, Eduard R. Felder, Antonella Isacchi, Daniele Donati, Arturo Galvani. NMS-P113, a novel orally available JAK2 selective inhibitor. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2015 Nov 5-9; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2015;14(12 Suppl 2):Abstract nr A179.

Use of natural clays as sorbent materials for rare earth ions: Materials characterization and set up of the operative parameters

Two mineral clays of the montmorillonite group were tested as sorbents for the removal of Rare Earths (REs) from liquid solutions. Lanthanum and neodymium model solutions were used to perform uptake tests in order to: (a) verify the clays sorption capability, (b) investigate the sorption mechanisms and (c) optimize the experimental parameters, such as contact time and pH. The desorption was also studied, in order to evaluate the feasibility of REs recovery from waters. The adsorption-desorption procedure with the optimized parameters was also tested on a leaching solution obtained by dissolution of a dismantled NdFeB magnet of a hard-disk. The clays were fully characterized after REs adsorption and desorption by means of X-ray powder diffraction (XRPD) and X-ray photoelectron spectroscopy (XPS); the liquid phase was characterized via Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES) analyses. The experimental results show that both clays are able to capture and release La and Nd ions, with an ion exchange mechanism. The best total efficiency (capture ≈ 50%, release ≈ 70%) is obtained when the uptake and release processes are performed at pH=5 and pH=1 respectively; in real leached scrap solutions, the uptake is around 40% but release efficiency is strongly decreased passing from a mono-ion system to a real system (from 80% to 5%). Furthermore, a strong matrix effect is found, with the matrix largely affecting both the uptake and the release of neodymium.

Pyrrole-3-carboxamides as potent and selective JAK2 inhibitors

We report herein the discovery, structure guided design, synthesis and biological evaluation of a novel class of JAK2 inhibitors. Optimization of the series led to the identification of the potent and orally bioavailable JAK2 inhibitor 28 (NMS-P953). Compound 28 displayed significant tumour growth inhibition in SET-2 xenograft tumour model, with a mechanism of action confirmed in vivo by typical modulation of known biomarkers, and with a favourable pharmacokinetic and safety profile.

Methods for the catalytic activation of metallic structured substrates

The review addresses the methods for depositing catalytic layers onto metallic structured substrates, specifically focusing on honeycomb monoliths and open-cell foams.

Identification of 4,5-dihydro-1H-pyrazolo[4,3-h]quinazoline derivatives as a new class of orally and selective Polo-like kinase 1 inhibitors

Polo-like kinase 1 (Plk1) is a fundamental regulator of mitotic progression whose overexpression is often associated with oncogenesis and therefore is recognized as an attractive therapeutic target in the treatment of proliferative diseases. Here we discuss the structure-activity relationship of the 4,5-dihydro-1H-pyrazolo[4,3-h]quinazoline class of compounds that emerged from a high throughput screening (HTS) campaign as potent inhibitors of Plk1 kinase. Furthermore, we describe the discovery of 49, 8-{[2-methoxy-5-(4-methylpiperazin-1-yl)phenyl]amino}-1-methyl-4,5-dihydro-1H-pyrazolo[4,3-h]quinazoline-3-carboxamide, as a highly potent and specific ATP mimetic inhibitor of Plk1 (IC(50) = 0.007 microM) as well as its crystal structure in complex with the methylated Plk1(36-345) construct. Compound 49 was active in cell proliferation against different tumor cell lines with IC(50) values in the submicromolar range and active in vivo in the HCT116 xenograft model where it showed 82% tumor growth inhibition after repeated oral administration.

Regulation of the Wild-Type and Y1235D Mutant Met Kinase Activation

Met receptor tyrosine kinase plays a crucial role in the regulation of a large number of cellular processes and, when deregulated by overexpression or mutations, leads to tumor growth and invasion. The Y1235D mutation identified in metastases was shown to induce constitutive activation and a motile-invasive phenotype on transduced carcinoma cells. Wild-type Met activation requires phosphorylation of both Y1234 and Y1235 in the activation loop. We mapped the major phosphorylation sites in the kinase domain of a recombinant Met protein and identified the known residues Y1234 and Y1235 as well as a new phosphorylation site at Y1194 in the hinge region. Combining activating and silencing mutations at these sites, we characterized in depth the mechanism of activation of wild-type and mutant Met proteins. We found that the phosphotyrosine mimetic mutation Y1235D is sufficient to confer constitutive kinase activity, which is not influenced by phosphorylation at Y1234. However, the specific activity of this mutant was lower than that observed for fully activated wild-type Met and induced less phosphorylation of Y1349 in the signaling site, indicating that this mutation cannot entirely compensate for a phosphorylated tyrosine at this position. The Y1194F silencing mutation yielded an enzyme that could be activated to a similar extent as the wild type but with significantly slower activation kinetics, underlying the importance of this residue, which is conserved among different tyrosine kinase receptors. Finally, we observed different interactions of wild-type and mutant Met with the inhibitor K252a that may have therapeutic implications for the selective inhibition of this kinase.

Structural characterization of the GSK-3beta active site using selective and non-selective ATP-mimetic inhibitors

GSK-3beta is a regulatory serine/threonine kinase with a plethora of cellular targets. Consequently, selective small molecule inhibitors of GSK-3beta may have a variety of therapeutic uses including the treatment of neurodegenerative diseases, type II diabetes and cancer. In order to characterize the active site of GSK-3beta, we determined crystal structures of unphosphorylated GSK-3beta in complex with selective and non-selective ATP-mimetic inhibitors. Analysis of the inhibitors' interactions with GSK-3beta in the structures reveals how the enzyme can accommodate a number of diverse molecular scaffolds. In addition, a conserved water molecule near Thr138 is identified that can serve a functional role in inhibitor binding. Finally, a comparison of the interactions made by selective and non-selective inhibitors highlights residues on the edge of the ATP binding-site that can be used to obtain inhibitor selectivity. Information gained from these structures provides a promising route for the design of second-generation GSK-3beta inhibitors.

Crystal structure of the tyrosine kinase domain of the hepatocyte growth factor receptor c-Met and its complex with the microbial alkaloid K-252a

The protooncogene c-met codes for the hepatocyte growth factor receptor tyrosine kinase. Binding of its ligand, hepatocyte growth factor/scatter factor, stimulates receptor autophosphorylation, which leads to pleiotropic downstream signaling events in epithelial cells, including cell growth, motility, and invasion. These events are mediated by interaction of cytoplasmic effectors, generally through Src homology 2 (SH2) domains, with two phosphotyrosine-containing sequence motifs in the unique C-terminal tail of c-Met (supersite). There is a strong link between aberrant c-Met activity and oncogenesis, which makes this kinase an important cancer drug target. The furanosylated indolocarbazole K-252a belongs to a family of microbial alkaloids that also includes staurosporine. It was recently shown to be a potent inhibitor of c-Met. Here we report the crystal structures of an unphosphorylated c-Met kinase domain harboring a human cancer mutation and its complex with K-252a at 1.8-A resolution. The structure follows the well established architecture of protein kinases. It adopts a unique, inhibitory conformation of the activation loop, a catalytically noncompetent orientation of helix alphaC, and reveals the complete C-terminal docking site. The first SH2-binding motif (1349YVHV) adopts an extended conformation, whereas the second motif (1356YVNV), a binding site for Grb2-SH2, folds as a type II Beta-turn. The intermediate portion of the supersite (1353NATY) assumes a type I Beta-turn conformation as in an Shc-phosphotyrosine binding domain peptide complex. K-252a is bound in the adenosine pocket with an analogous binding mode to those observed in previously reported structures of protein kinases in complex with staurosporine.

Basic fibroblast growth factor stimulates hepatocyte growth factor/scatter factor secretion by human mesenchymal cells

Basic fibroblast growth factor (bFGF) together with other pleiotropic factors plays an important role in many complex physiological processes such as embryonic development, angiogenesis, and wound repair. Among these factors, hepatocyte growth factor/scatter factor (HGF/SF) which is secreted by cells of mesodermal origin exerts its mito- and motogenic activities on cells of epithelial and endothelial origin. Knowledge of the regulatory mechanisms of HGF/SF may contribute to the understanding of its role in physio-pathological processes. We observed that the secretion of HGF/SF by MRC-5 cells and by other fibroblast-derived cell cultures in conditioned media was enhanced by exposure to bFGF. HGF/SF was measured by the scatter assay, a bioassay for cell motility, and was further characterized by Western blot analysis with anti-HGF/SF antibodies. Exposure of MRC-5 cultures to 10 ng/ml of bFGF resulted already 6 h posttreatment in a threefold higher amount of scatter factor secreted into the medium as compared to untreated cultures. HGF/SF secretion was sustained after bFGF treatment for the following 72 h when increased amounts of HGF/SF were detected both in conditioned media as well as associated to the extracellular matrix. The secretion of HGF/SF in cell supernatants increased dose dependently upon treatment with bFGF starting from basal levels of 6 U/ml and reaching 27 U/ml at 30 ng/ml bFGF, plateauing thereafter. Upregulation of HGF/SF by IL-1, already described by others, was confirmed in this study. Based on our findings an articulated interaction can be speculated for bFGF, HGF/SF, and IL-1, e.g., in tissue regeneration during inflammatory processes or in wound healing.

Suramin modulates cellular levels of hepatocyte growth factor receptor by inducing shedding of a soluble form

Several growth factor receptors undergo shedding from the cell surface as a result of limited proteolysis via mechanisms that are at present poorly understood. By Western blotting of the conditioned media and cell lysates of several cell lines expressing the hepatocyte growth factor receptor, we found that suramin, a pharmacological agent that inhibits the activity of many growth factors, was able to induce shedding of this receptor. Increased levels of soluble hepatocyte growth factor receptor were observed in the conditioned media of GTL-16, a cell line over-expressing the receptor, as early as ten minutes after initial exposure to the agent, and incubation of this line with 300 microM suramin caused a 50% reduction in cell-associated levels of receptor after 6 hours. Although protein kinase C activation by treatment of cells with phorbol esters has previously been found to stimulate shedding of the hepatocyte growth factor receptor, this hitherto undescribed activity of suramin was not affected by protein kinase C inhibitors. Since shedding represents a possible means of down-modulation of receptor activity, suramin may inhibit the hepatocyte growth factor ligand/receptor system, not only by abrogation of hepatocyte growth factor binding to intact receptor, but also by induction of receptor shedding.

D-amino acid scan of endothelin: importance of amino acids adjacent to cysteinyl residues in isomeric selectivity

A systematic approach to map the functionally important determinants of endothelin-1 (ET-1) by a D-amino acid scan is described. Correct orientation of the amino acid side chains was generally of paramount importance both for binding at the ETA receptor and for contracting activity. This was particularly valid for positions 2, 8, 14, 16-21 (the four Cys residues were kept unaltered). Nevertheless, increment of binding affinity was observed by inversion of configuration at positions 6, 7, 9 and 10. In addition, [D-Lys9]ET was an agonist about four times more potent than the natural compound. Usually both 1,4- and 1,3-isomers (corresponding, respectively, to the correct and misfolded disulfide bridges of ET) were obtained, and usually the isomer formed in larger amount had the higher HPLC retention time and the higher biological activity. However, four out of seventeen single-point D-amino acid analogues could be isolated only in one isomeric form. In three cases (D-Ser2, D-Ser4, D-Val12), the inverted amino acid was adjacent to a Cys residue, and in one case (D-Lys9) it was one amino acid apart, thus suggesting a possible effect of the bridged cysteinyl residues in isomeric selectivity.

Endothelin-1-selective binding sites are downregulated by transforming growth factor-beta and upregulated by basic fibroblast growth factor in a vascular smooth muscle-derived cell line

Endothelins (ETs) elicit in vivo and in vitro a potent vasoconstrictor activity after binding to high-affinity receptors on vascular smooth muscle cells (VSMC). A617 cells, a VSM-derived cell line, were used as an in vitro model system to study selected growth factors and cytokines involved in proliferative and/or inflammatory diseases of the vessel wall as possible regulators of the high-affinity binding capacity of ET-1 to the cells. Radioligand studies characterized the binding of ET-1 to the isopeptide selective ETA receptor subtype on A617 cells as a time- and temperature-dependent saturable process (Kd = 0.13 +/- 0.04 nM, Bmax = 49 +/- 7 fmol/10(6) cells). Pretreatment of A617 cells with basic fibroblast growth factor (bFGF), a mitogenic agent for vascular cells, resulted in a time- and dose-dependent increase in ET-1 binding capacity, whereas preexposure to transforming growth factor-beta (TGF-beta) induced a reduction of the Bmax for ET-1. Platelet-derived growth factor (PDGF), interleukin-6 (IL-6), tumor necrosis factor-alpha, and fetal bovine serum (FBS) pretreatments did not affect consequent ET-1 binding to A617 cells.

Alanine scan of endothelin: importance of aromatic residues

A systematic approach to map the functional important determinants of endothelin-1 (ET) by an alanine scan is described. Studies on the in vitro receptor binding affinity and on the agonist contracting activity defined that residues Asp8, Tyr13, Phe14, Leu17, and Trp21 were of major biological significance. A striking observation was that four out of these five sites were hydrophobic amino acids. Ala analogues of the aromatic residues at position 13, 14, and 21 displayed sharply reduced receptor binding affinity (< 2% of ET) and can be considered important for receptor contact. Ala analogues of Asp8 and Leu17 lost most (> 90%) of the agonist activity but retained a receptor affinity nearly equivalent to ET and can be considered to be important for signal transduction. Three other positions, Val12, Asp18, and Ile20 (which are adjacent to the biologically important sites of Tyr13, Leu17, and Trp21), resulted as partially tolerant to Ala substitution, retaining 14-50% of the potency of ET. Ala analogues of the Et isomeric disulfide arrangement (Cys1,11 and Cys3,15) were always less active than the corresponding analogues with the native disulfide pairings (Cys1,15 and Cys3,11).

Lack of immunization after intraperitoneal insemination of spermatozoa

Twenty infertile patients with normal tubal patency were inseminated intraperitoneally (11 once, seven twice, and two three times) with spermatozoa (mean 14 x 10(6), range 0.6-48 x 10(6)) prepared by the standard swim-up technique. The occurrence of immunization to spermatozoa was looked for by the Gelatin Agglutination Test (GAT) and Tray Agglutination Test (TAT). Both tests gave negative results for all the controls (10 pregnant and 10 puerperal women). Antisperm antibodies were measured in the serum before, 30 d and 4-7 months after Intraperitoneal Insemination (IPI). The last check was done for only 14 patients, since six became pregnant as a consequence of the first treatment. Of the 14 patients studied after 4-7 months, seven had two, and two had three IPI. In the group of inseminated patients, 18 women with no basal sperm antibody did not show evidence of antibody formation after the treatment and it was not increased after insemination in the two patients who already had low antibody titre (1/32). In conclusion, despite the large number of spermatozoa inseminated and even after several IPI attempts, there was no evidence of de novo production of or increase in already present anti-sperm antibodies according to the methods used for the detection of ASA in this study.

Stabilization of recombinant human basic fibroblast growth factor by chemical modifications of cysteine residues

The production of recombinant human basic fibroblast growth factor (rhbFGF) in Escherichia coli cells yielded active forms of this polypeptide which, however, displayed a high degree of instability towards oxidative processes. Biochemical studies in our laboratory and those of others indicated that the reactivity of the four cysteine residues was the main cause of the observed instability. Several attempts to obtain more stable derivatives of rhbFGF were carried out by modification of the sulfhydryl groups. Among these, treatment of rhbFGF with iodoacetic acid led to the isolation of a partially carboxymethylated form (Cm-FGF). Peptide mapping analysis of the modified protein showed that two cysteines (78 and 96) were blocked by a carboxymethyl group. The remaining cysteines (34 and 101) were not modified under the conditions used and were found to be in the reduced form. Cm-FGF and unmodified rhbFGF showed similar affinity both for heparin and for high-affinity receptors. Cm-FGF was more stable than the unmodified molecule as measured by HPLC and SDS/PAGE analysis. Interestingly, Cm-FGF was more active than unmodified rhbFGF in stimulating proliferation of endothelial cells and DNA synthesis in 3T3 fibroblasts. This new derivative could represent a desirable complementation to rhbFGF for the development of more stable pharmaceutical formulations in wound healing applications.

Pregnancy after direct intraperitoneal insemination of spermatozoa from a man with severe infertility, after unsuccessful application of other methods of assisted fertilization

Direct intraperitoneal insemination (DIPI) is one of the least invasive strategies of assisted reproduction. Unexplained infertility and male sub-fertility are the major indications for DIPI. It is otherwise well known that assisted procreation gives poor results in severe male infertility. This is a report of a pregnancy that occurred as a result of a direct intraperitoneal insemination of prepared spermatozoa characterized by a particularly severe astheno-teratozoospermia in a couple unsuccessfully treated with other, more invasive methods of assisted fertilization.

IVF: induction of ovulation in poor responders

All IVF programs have a consistent rate of failure in inducing ovulations. Pharmacological induction of ovulation is otherwise crucial for an IVF program because of the need for more than one ovum. Since it is well known that the best candidates for HMG treatment are hypogonadotropic women a short reversible hypogonadotropic state was induced in IVF patients by LH-RH agonist (Buserelin). Superovulation was then achieved with very high initial doses of FSH (Metrodin) in order to maximize the ovarian response. This technique used in 116 IVF women induced a satisfactory follicle growth even in 70% of the patients already poorly responsive to HMG stimulation.

Ovarian stimulation of IVF patients: effects of the reversible hypogonadotrophic state induced by GnRH agonist

Multiple ovulation was induced in 122 hypogonadotrophic IVF patients with large doses of HMG. The hypogonadotrophic state, short and reversible, was obtained by nasal administration of a GnRH agonist (200 micrograms, five times per day). In the 97 induced cycles, a mean of 9.1 follicles was recorded. A comparison of the results obtained for 36 patients who had already been treated with clomiphene and HMG showed both significantly more follicles per cycle (8.5 versus 3.0) and an increase in oocytes retrieved (6.7 versus 1.3) when treated with the agonist and HMG. In addition 11 of 18 already poorly responsive patients had normal responses. The luteal phase was supported by either HCG or progesterone injection. Plasma progesterone profiles were satisfactory and, as expected, the highest progesterone concentrations were associated with HCG treatment.